Bursitis is defined as inflammation that a bursa. Human beings have approximately 160 bursae. These are saclike structures in between skin and bone or in between tendons, ligaments, and bone. The bursae room lined by synovial tissue, i m sorry produces liquid that lubricates and also reduces friction in between these structures.

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Bursitis occurs once the synovial lining i do not care thickened and produces extreme fluid, leading to localized swelling and also pain. <1, 2, 3> The complying with bursae room most typically affected:

Routine activities blood occupational is typically not advantageous in the diagnosis of noninfectious bursitis but is suitable when septic bursitis or underlying autoimmune condition is suspected. Aspiration and evaluation of bursal fluid should be done to rule out infectious or rheumatic causes and also may also be therapeutic.

MRI is typically unnecessary however if necessary is very sensitive because that identification the bursitis, and can rule out suspected solid tumors and also define pathology for possible surgical excision. Ultrasonography is valuable for further imaging of the bursa once the diagnosis is uncertain, and also can overview diagnostic aspiration or therapeutic injections.

Conservative treatment to mitigate inflammation is offered for many patients v bursitis and includes the following:

Patients v suspected septic bursitis have to be treated v antibiotics while awaiting society results. Surgical excision of bursae might be required as a last resort for chronic or typically recurrent bursitis.

Bursae room flattened bag that serve as protective buffers between bones and also overlapping muscles (deep bursae) or between bones and tendons or skin (superficial bursae). This synovial-lined sacs space filled v minimal quantities of liquid to facilitate movement throughout muscle contraction. Deep bursae (eg, subacromial and iliopsoas bursae) are situated in the fascia. Superficial bursae (eg, olecranon and also prepatellar bursae) are situated in the subcutaneous tissue.

There space two species of bursae: constant and adventitial. Both types can be affiliated in acute or chronic bursitis. Constant bursae have the adhering to characteristics:

Adventitial bursae (examples include those that build over a bunion and osteochondroma) have actually the adhering to characteristics:

All the the roughly 160 bursae in the human body are perhaps susceptible come injury. The three upper-extremity bursae the are many commonly affected by bursitis space the subacromial, subscapular, and olecranon bursae. <4>

The subacromial bursa the end the premium surface that the supraspinatus tendon from the overlying coracoacromial arch and also the deltoid muscle. It lies in between the acromion and the rotator cuff and cushions the coracoacromial ligament native the supraspinatus muscle. As soon as the eight is resting at the side, the bursa protrudes laterally from beneath the acromion; once the eight is abducted, the rolls medially beneath the bone. Check out the picture below.

Subscapular bursae room found in between the anterior surface ar of the scapula and also the posterior chest wall. The 2 commonly influenced bursae are situated superomedially in between the serratus anterior and the chest wall. Check out the image below.

Shoulder anatomy muscle, anterior view.

Two olecranon bursae can come to be inflamed; one lies between the tendon that the triceps and the posterior ligament the the elbow and the olecranon, conversely, the various other is an ext superficial, lying in between the attachments of the triceps come the olecranon and the skin.

Various lower-extremity bursae can additionally be influenced by bursitis. The ones many commonly involved are in the hip, the knee, and also the ankle. <5, 6, 7>

In the hip, the ischiogluteal bursa lies deep come the gluteus maximus end the ischial tuberosity. The iliopsoas bursa, the largest bursa in the body, lies in between the iliopsoas tendon and the lesser trochanter, prolonging upward right into the iliac fossa in ~ the iliacus. The trochanteric bursa has superficial and also deep components, with the superficial bursa lying between the tensor fascia latae and the skin and the deep bursa located between the better trochanter and also the tensor fasciae latae.

In the knee, bursae commonly affected by bursitis encompass the medial collateral ligament bursa, the anserine (pes anserinus) bursa (see the image below), the prepatellar bursa (located anteriorly over the patella, between patella and also skin), the infrapatellar bursa (containing a superficial component lying in between the patellar ligament and the skin and also a deep component lying in between the patellar ligament and also the proximal anterior tibia), and also the popliteal bursae, or Baker cysts (located in the posterior share capsule the the knee). <6>

location of anserine (pes anserinus) bursa on medial knee. MCL=medial collateral ligament.
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In the ankle, two bursae are found at the level that insertion the the Achilles tendon. The superficial one is located in between the skin and the tendon, and also the deep one is located in between the calcaneus and the tendon. The latter is the one much more commonly influenced by bursitis.



Inflammation of the bursa causes synovial cell to multiply and thereby increases collagen formation and fluid production. A much more permeable capillary membrane permits entrance that high protein fluid. The bursal lining may be changed by granulation tissue adhered to by fibrous tissue. The bursa i do not care filled with fluid, i beg your pardon is frequently rich in fibrin, and the fluid can end up being hemorrhagic. <8> One study says that this process may be mediated by cytokines, metalloproteases, and cyclooxygenases.

In septic arthritis, neighborhood trauma usually reasons inoculation that bacteria into the bursa, i beg your pardon triggers the inflammation process.

There space three phases that bursitis: acute, recurrent, and also chronic. <9> during the acute phase of bursitis, local inflammation occurs and the synovial fluid is thickened, and movement i do not care painful together a result. Chronic bursitis leader to continual pain and can cause weakening the overlying ligaments and tendons and, ultimately, rupture that the tendons. Since of the feasible adverse effects of chronic bursitis top top overlying structures, bursitis and tendinitis may happen together; the differential diagnosis should encompass both of these diagnoses.

Upper-extremity bursitis

Subacromial bursitis

The subacromial bursa facilitates activity of the supraspinatus tendon and becomes inflamed an additional to repeated overuse injury the this tendon. Subacromial bursitis is regularly coexistent v supraspinatus tendinitis and also partial- or complete-thickness tears the the supraspinatus tendon (1 the the 4 tendons comprising the rotator cuff). <10>

Subscapular bursitis

Subscapular bursae end up being inflamed as a an outcome of abnormal bony frameworks or soft-tissue alters that influence the activity of the scapula end the posterior chest wall.

Olecranon bursitis

The an ext superficial the the 2 olecranon bursae commonly connected in bursitis is predisposed to straight trauma or accumulation microtrauma from activities requiring constant elbow movement (eg, swimming, skiing, gymnastics, and also weightlifting). This kind of bursitis is frequently recurrent. <11, 12, 13>

Olecranon bursitis, presented here v elbow flexed. Picture courtesy the UMDNJ-New Jersey medical School, www.DoctorFoye.com, and also www.TailboneDoctor.com.
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Lower-extremity bursitis

Bursitis that hip

Ischiogluteal bursitis is connected with sedentary occupations and is brought about by direct stress on the bursa (hence the nickname “weaver’s bottom”). Patients have actually pain v sitting and walking and have localized tenderness over the ischial tuberosity. Physical examination often reveals pain through passive i know good flexion and resisted i know good extension.

Iliopsoas bursitis arises once a defect develops in the anterior part of the hip share capsule, enabling communication that the joint v the bursa. The is often connected with i know good pathology (eg, rheumatoid arthritis or osteoarthritis) or entertain injury (eg, running). Epidemic of the iliopsoas bursa is rare.

Greater trochanter bursitis is common in overweight middle-aged women and also is connected with acute trauma, overuse, and also mechanical factors. The clinical presentation is the deep, aching lateral hip pain that might radiate into the buttocks or lateral knee. Pains is worse with task and stretching and may it is in worse in ~ night, especially when the patient lies on the impacted side. Palpation end the better trochanter elicits major tenderness. Physics examination reveals pains with resisted hip abduction and external rotation. <14, 15, 16, 17>

Bursitis that knee

The medial collateral ligament bursa is most frequently injured second to a twisting injury with external tibial rotation. Medial joint heat pain occurs and also may limit knee extension. This may be confused with a meniscal tear on physical examination.

Anserine (pes anserinus) bursitis is no usually connected with overuse but may happen in patients with medial compartmental osteoarthritis. Clinically, patient complain the pain and tenderness end the anteromedial knee the is worse with knee flexion. This condition may be perplexed with medial meniscal pathology. <18, 19>

Prepatellar bursitis, likewise known as housemaid’s knee, is linked with trauma or with repeated kneeling over an extended period. The prepatellar bursa is additionally a common site for septic (infectious) bursitis, a diagnosis that should be considered when there is skin injury, erythema, warmth, or serious tenderness over the patella. In patients with septic prepatellar bursitis, the patella is no palpable, and knee flexion is painful.

Popliteal bursae (Baker cysts) are linked with local swelling and pain on walking, jumping, and also squatting. Magnetic resonance imaging (MRI) or ultrasonography can distinguish an isolated bursitis indigenous intra-articular injury. (See additionally Baker Cyst.)

Bursitis of ankle

Retrocalcaneal bursitis is typically caused by regional trauma from poorly design shoes. Patient complain the posterolateral heel pain and also may have a posterior heel prestige (“pump bump”), and also local swelling and tenderness over the Achilles tendon. Pains is boosted by squeezing the bursa from side to side and anterior come the Achilles. A hoe lift and also open-back shoes help alleviate pressure. <20>



Bursitis has plenty of causes, including autoimmune disorders, crystal deposition (gout and pseudogout), contagious diseases, traumatic events, and hemorrhagic disorders, and being secondary to overuse. Recurring injury within the bursa results in neighborhood vasodilatation and also increased vascular permeability, which stimulate the inflammation cascade.Subdeltoid and also subacromial bursitis have been reported after vaccination, when poor technique results in direct injection of the vaccine into the bursa. <21>

The following systemic illness have also been linked with bursitis:

Hypertrophic pulmonary osteoarthropathy
Idiopathic hypereosinophilic syndrome

In addition, bursitis and also other soft-tissue disorders have been linked with generalised hypermobility. Some rheumatic conditions, such together gout, have the right to predispose patients to bursitis.

Septic (infectious) bursitis is most common in superficial bursae. In the majority (50-70%) that cases, it outcomes from direct introduction of microorganisms through traumatic injury or through contiguous spread out from cellulitis (50-70% of cases). Much less commonly, epidemic of deep bursae is because of contiguous septic arthritis or bacteremia (10% that cases).

The most common causative biology is Staphylococcus aureus (80% the cases), adhered to by streptococci. However, many other organisms have been implicated in septic bursitis, including mycobacteria (both tuberculous and also nontuberculous strains), fungi (Candida), and algae (Prototheca wickerhamii). <22> A instance ofolecranon bursitiscaused byBrucella melitensis has to be reported. <23>

Factors predisposing come infection include diabetes mellitus, steroid therapy, uremia, alcoholism, skin disease, and trauma. A background of noninfectious inflammation of the bursa also increases the risk of septic bursitis.

A situation ofmethicillin-resistantStaphylococcus aureus (MRSA)-caused septic bursitis was reported in aninjection medicine user following an effort to inject drugs right into the soft organization of the knee. <24>


Epidemiology and Prognosis

Bursitis accounts because that 0.4% of all visits come primary treatment clinics. The most typical locations the bursitis room the subdeltoid, olecranon, ischial, trochanteric, and prepatellar bursae.

The incidence the bursitis is greater in athletes, reaching levels together high as 10% in runners. Approximately 85% of cases of septic superficial bursitis happen in men. A French research aimed in ~ assessing the prevalence of knee bursitis in the working populace found that most cases developed in male workers whose occupations involved heavy workloads and frequent kneeling. <25>

Mortality in patients v bursitis is an extremely low. The prognosis is good, v the vast majority of patients receiving outpatient follow-up and treatment.

Clinical Presentation

DeLee JC, Drez D. Imaging effusions, cysts, and also ganglia. DeLee JC, Drez D, fearbut MD, eds. DeLee and also Drez’s Orthopaedic sporting activities Medicine: Principles and also Practice. Philadelphia: WB Saunders; 2003. 1646-8.

Keplinger FS, Gupta N. :. Knee bursitis. Frontera WR, silver JK, eds. Essentials of physical Medicine and Rehabilitation. 340-4. Philadelphia: Hanley & Belfus; 2002.

Media gallery
Olecranon bursitis, displayed here through elbow flexed. Picture courtesy the UMDNJ-New Jersey medical School, www.DoctorFoye.com, and www.TailboneDoctor.com.
Olecranon bursitis: aspiration that hemorrhagic effusion. Image courtesy of UMDNJ-New Jersey medical School, www.DoctorFoye.com, and www.TailboneDoctor.com.
place of anserine (pes anserinus) bursa ~ above medial knee. MCL=medial collateral ligament.
Acute infectious bursitis upon presentation to emergency department. Image courtesy of Christopher Kabrhel, MD.
contagious bursitis. Image courtesy the Christopher Kabrhel, MD.
Shoulder anatomy muscle, anterior view.
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Contributor Information and Disclosures

Kristine M Lohr, MD, MSProfessor, department of interior Medicine, Interim Chief, department of Rheumatology, Director, Rheumatology cultivate Program, college of Kentucky university of Medicine Kristine M Lohr, MD, multiple sclerosis is a member of the complying with medical societies: American university of Physicians, American university of RheumatologyDisclosure: Nothing come disclose.


Alita Gonsalves, MDPhysiatrist, exclusive Practice, Vero Orthopaedics and Neurology; former Staff Physician, room of physical Medicine and also Rehabilitation, new York Presbyterian Hospital Alita Gonsalves, MD is a member the the following medical societies: American Academy of physical Medicine and Rehabilitation, Physiatric association of Spine, Sports and Occupational RehabilitationDisclosure: Nothing to disclose.

Leon Root, MDProfessor that Clinical Surgery, department of Orthopedics, Weill medical College of Cornell University; Founder and also Director, Pediatric Outreach Program; Emeritus chef of Osteogenesis Imperfecta Clinic, Attending Orthopedic Surgeon, medical Director of Rehabilitation, Emeritus cook of Pediatric Orthopedics, The Hospital because that Special surgical procedure Leon Root, MD is a member of the following medical societies: American Academy that Orthopaedic Surgeons, American Orthopaedic Association, new York Academy that Medicine, American Academy the Cerebral Palsy and Developmental Medicine, Pediatric Orthopaedic culture of north AmericaDisclosure: Nothing to disclose.

Janet Kay Talbot-Stern, MD, FACEM, FCEMEmergency medicine VMO, Ryde and also Bankstown Hospitals, Australia Locum Consultant, St thomas Hospital, UKDisclosure: Nothing to disclose.

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Herbert S Diamond, MDVisiting Professor that Medicine, division of Rheumatology, State college of brand-new York Downstate medical Center; Chairman Emeritus, room of inner Medicine, west Pennsylvania Hospital Herbert S Diamond, MD is a member that the complying with medical societies: Alpha Omega Alpha, American college of Physicians, American university of Rheumatology, American clinical Association, Phi Beta KappaDisclosure: Nothing come disclose.


Ian D Dickey, MD, FRCSC Adjunct Professor, department of Chemical and Biological Engineering, university of Maine; Consulting Staff, Adult Reconstruction, Orthopedic Oncology, department of Orthopedics, eastern Maine medical Center

Ian D Dickey, MD, FRCSC is a member that the following medical societies: American Academy of Orthopaedic Surgeons, british Columbia clinical Association, Canadian medical Association, and Royal college of Physicians and Surgeons the Canada

Disclosure: Stryker Orthopaedics Consulting dues Consulting; Cadence Honoraria Speaking and also teaching

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Mark Louden, MD Assistant Professor of Clinical Medicine, division of Emergency Medicine, room of Medicine, college of Miami, Leonard M Miller institution of Medicine

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Heidi M Stephens, MD, MBA associate Professor, department of Surgery, division of Orthopedic Surgery, university of south Florida college of Medicine; Courtesy share Associate Professor, room of Environmental and Occupational Health, college of south Florida college of windy Health

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